I believe the Nikon Df has pretty all AF lenses and maybe some MF lenses that will will on the camera. Nikon is a more complete system as is Canon vs anything mirrorless.

Sensor size does matter a lot and I'd say the same if you were comparing Micro Four Thirds and after shooting Nikon then Panasonic GH-3 with their fast glass and now Fuji each has their place.

I have handled the Nikon Df and regardless of all the guts etc, I did not care for the hand grip, minor but a functional concern.

As far as Fuji goes I need to use an accessory hand grip because I find the Fuji cameras too shallow when it comes to the camera as is, grip.

The obvious is larger DSLR lenses, they cost more etc..

If Fuji does not do more with the X200 or Xpro-2 rumored getting a DSLR or even micro four thirds again to use in tandem with Fuji may happen. I just won't invest as heavily in Fuji glass, like 4 -5 lenses.

My issue is with lack of accessories for Fuji, if Metz did a flash that would be more than OK. I understand the XT-1 is an improvement but it is not a DSLR killer yet, hope it will be.